%
%?FUNCTION?1.2?:?“cp0101_bandwidth“
%
%?Evaluates?the?bandwidth?of?the?input?‘signal‘?with?sampling?period
%?‘dt‘
%?Bandwidth?is?evaluated?according?to?the?given?‘threshold‘?（in?dB）
%?‘BW‘?is?the?bandwidth
%?‘f_high‘?is?the?higher?limit
%?‘f_low‘?is?the?lower?limit
%
%?Programmed?by?Guerino?Giancola
%

function?[ss_Ef_highf_lowBW]?=?...
???cp0101_bandwidth（signaldtthreshold）

%?---------------------------------------------
%?Step?One?-?Evaluation?of?the?single-sided?ESD
%?---------------------------------------------

fs?=?1?/?dt;?????????%?sampling?frequency
N?=?length（signal）;??%?number?of?samples?（i.e.?size?of?the?FFT）
T?=?N?*?dt;??????????%?time?window
df?=?1?/?T;??????????%?fundamental?frequency

X?=?fft（signal）;?%?double-sided?MATLAB?amplitude?spectrum
X?=?X/N;?????????%?conversion?from?MATLAB?spectrum?to?fourier?spectrum
ds_E?=?abs（X）.^2/（df^2）;??????%?double-sided?ESD
ss_E?=?2.*ds_E（1:floor（N/2））;?%?single-sided?ESD

%?------------------------------------------------
%?Step?Two?-?Evaluation?of?the?frequency?bandwidth
%?------------------------------------------------

[Epeakindex]?=?max（ss_E）;??????%?Epeak?is?the?peak?value?of?the?ESD
f_peak?=?index?*?df;????????????%?peak?frequency???

Eth?=?Epeak*10^（threshold/10）;??%?Eth?is?the?value?of?the?ESD
????????????????????????????????%?corresponding?to?the?given
????????????????????????????????%?threshold

%?iterative?algorithm?for?evaluating?high?and?low?frequencies

imax?=?index;
E0h?=?ss_E（index）;

while?（E0h>Eth）&（imax<=（N/2））

????imax?=?imax?+?1;
????E0h?=?ss_E（imax）;

end?%?while?E0h?>?Eth

f_high?=?（imax-1）?*?df;?????????????%?high?frequency

imin?=?index;
E0l?=?ss_E（index）;

while?（E0l>Eth）&（imin>1）&（index>1）

????imin?=?imin?-?1;
????E0l?=?ss_E（imin）;

end?%?while?E0l?>?Eth

f_low?=?（min（indeximin）-1）?*?df;???%?low?frequency

%?end?of?iterative?algorithm

BW?=?f_high?-?f_low;????????????%?signal?frequency?bandwidth

fprintf（‘\nFrequency?Bandwidth?=?%f?[Hz]\nHigh?Frequency?=?%f?[Hz]\nLow?Frequency?=??%f?[Hz]\n‘BWf_highf_low）;

%?-----------------------------
%?Step?Three?-?Graphical?output
%?-----------------------------

figure（2）

frequency=linspace（0fs/2length（ss_E））;
PF=plot（frequencyss_E）;
set（PF‘LineWidth‘[2]）;
L1=line（[f_high?f_high][min（ss_E）?max（ss_E）]）;
set（L1‘Color‘[0?0?0]‘Linestyle‘‘:‘）
L1=line（[f_low?f_low][min（ss_E）?max（ss_E）]）;
set（L1‘Color‘[0?0?0]‘Linestyle‘‘:‘）
L1=line（[f_low?f_high][Eth?Eth]）;
set（L1‘LineWidth‘[2]‘Color‘‘red‘‘Linestyle‘‘:‘）
axis（[0.8*f_low?1.2*f_high?-0.1*Epeak?1.2*Epeak]）;
AX?=?gca;
set（AX‘FontSize‘12）;
T=title（‘Frequency?domain‘）;
set（T‘FontSize‘14）;
X=xlabel（‘Frequency?[Hz]‘）;
set（X‘FontSize‘14）;
Y=ylabel（‘Single-Sided?ESD??[V^2s/Hz]‘）;
set（Y‘FontSize‘14）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件?????886112??2009-01-07?10:03??_超寬帶無線電基礎\Capacity?of?pulse-position?modulation（PPM）?on?Gaussian?and?Webb?channels.pdf

?????文件???????2945??2004-03-06?01:47??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0101\CP0101_BANDWIDTH.M

?????文件???????1230??2004-03-06?01:45??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0101\CP0101_GENRECT.M

?????文件???????2967??2004-03-06?01:49??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0102\CP0102_SINPULSE_ONE.M

?????文件???????2973??2004-03-06?01:51??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0102\CP0102_SINPULSE_TWO.M

?????文件???????1841??2004-03-06?05:30??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0201\CP0201_2PPM_TH.M

?????文件????????410??2004-03-06?01:54??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0201\CP0201_BITS.M

?????文件????????643??2004-03-06?01:55??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0201\CP0201_REPCODE.M

?????文件????????364??2004-03-06?01:56??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0201\CP0201_TH.M

?????文件???????3847??2004-03-06?05:39??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0201\CP0201_TRANSMITTER_2PPM_TH.M

?????文件???????1411??2004-03-06?05:31??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0201\CP0201_WAVEFORM.M

?????文件???????1542??2004-03-06?05:45??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0202\CP0202_2PAM_DS.M

?????文件????????348??2004-03-06?05:41??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0202\CP0202_DS.M

?????文件???????3270??2004-03-06?05:47??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0202\CP0202_TRANSMITTER_2PAM_DS.M

?????文件???????3939??2004-03-06?05:51??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0203\CP0203_OFDM_QPSK.M

?????文件????????741??2004-03-06?05:49??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0203\CP0203_QPSK_MOD.M

?????文件???????1965??2004-03-06?04:43??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0301\CP0301_PPM_SIN.M

?????文件????????993??2004-03-06?04:44??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0301\CP0301_PSD.M

?????文件???????1703??2004-03-06?04:45??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0302\CP0302_PPM_PERIODIC.M

?????文件???????2113??2004-03-06?04:49??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0303\CP0303_PPM_RANDOM.M

?????文件???????1572??2004-03-06?04:52??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0402\CP0402_2PAM_TH.M

?????文件???????3652??2004-03-06?04:54??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0402\CP0402_TRANSMITTER_2PAM_TH.M

?????文件???????1007??2004-03-06?05:01??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0602\CP0602_GAUSSIAN_PSD_NTH.M

?????文件???????3175??2004-03-06?04:58??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0602\CP0602_link_BUDGET.M

?????文件???????1031??2004-03-06?05:00??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0602\CP0602_MAX_DISTANCE.M

?????文件???????1629??2004-03-06?04:56??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0602\CP0602_SYMBOL_ERROR_PROBABILI.M

?????文件???????2044??2004-03-06?05:02??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0602\CP0602_THR_DB_VECTORS.M

?????文件???????3530??2004-03-06?05:06??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0701\CP0701_SHAPE_FACTOR_VARIATION.M

?????文件???????3934??2004-03-06?05:09??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0702\CP0702_ANALYTICAL_WAVEFORMS.M

?????文件???????1997??2004-03-06?05:17??_超寬帶無線電基礎\M文件\超寬帶無線電基礎M文件\CDROM\CP0702\CP0702_BANDWIDTH.M

............此處省略103個文件信息